This invention relates to electronic control of infection, and more particularly to a new and improved electronic method and apparatus for killing plant and animal bacteria and plant viroids.
Nearly a century of experience has demonstrated the effectiveness of silver metal and silver salts against infection. Bolton in 1894 and Halstead in 1913 described the use of silver foil on fresh wounds to inhibit the growth of microorganisms, and argerol and silver nitrate were common bactericidal agents a decade or two ago.
The results have never been spectacular and silver therapy has drifted out of clinical use. The very low solubility of silver and of many silver salts in aqueous solution permits only a very low concentration of the Ag+ ion. Spadero in 1974 showed this highly oxidizing ion to be the effective germicidal agent, demonstrated a much higher concentration of the ion by anodically corroding metallic silver, and reported killing a broad spectrum of animal bacteria with as little as 400 nanoamperes of anodic DC current.